This page shows a computer drawing of the Wright brothers’ 1904 aircraft. This machine was the second powered aircraft built by the brothers. The forces acting on this aircraft are identical to the forces which act on any modern aircraft. Following the successful first flights at Kitty Hawk on December 17, 1903, the brothers returned to Dayton, Ohio. On each of the four flights of that day, the 1903 aircraft exhibited an instability in pitch: the nose, and consequently the entire aircraft, would slowly bounce up and down. On the last flight, hard contact with the ground broke the front elevator support.
Please note: the simulation below is best viewed on a desktop computer. It may take a few minutes for the simulation to load.
They built a new engine similar to the 1903 engine but increased the power from 12 horsepower to 18 horsepower by slightly increasing the bore (diameter of the piston). They also built a new airframe with redesigned rudders. The new aircraft was to be flown from a cow pasture owned by Torrence Huffman and located just outside Dayton.
Without the winds of Kitty Hawk, it was a problem getting enough airspeed to fly. So the brothers devised a catapult system to help launch the aircraft. Once airborne, the aircraft experienced the same pitch problems as the 1903 aircraft. In an effort to solve the problem, they moved the radiator and fuel tank from the front struts to the rear struts and moved the engine slightly aft to move the aircraft center of gravity aft. But this only made the pitch problem worse. So the brothers added 70 pounds of iron bars as ballast to the front elevator to move the center of gravity farther forward. The weight of the aircraft then increased to about 900 pounds with the pilot. The ballast improved the handling of the aircraft and Wilbur was able to complete the first circuit of the airfield on September 20, 1904.
By the end of the year, the plane could complete four circuits and stay in the air for five minutes, but the aircraft still had major handling problems and it was overweight. It would take one more re-design in 1905 before the Wrights would have a fully operational aircraft.